Geoffrey R Atelu1,2, Nancy O Duah3, Michael D Wilson4. 1. Ghana Field Epidemiology and Laboratory Training Program, School of Public Health, College of Health Sciences, University of Ghana, Legon, Ghana. 2. Ghana Health Service, Accra, Ghana. 3. Epidemiology Department, Noguchi Memorial Institute for Medical Research, University of Ghana, P. O. Box LG 581, Legon, Ghana. 4. Parasitology Department, Noguchi Memorial Institute for Medical Research, University of Ghana, P. O. Box LG 581, Legon, Ghana.
Abstract
BACKGROUND: We investigated the prevalence of sub-microscopic Plasmodium falciparum infections and gametocyte carriage in asymptomatic individuals in Navrongo in northern Ghana, an area of seasonal malaria transmission. DESIGN: A cross sectional study of 209 randomly selected participants of all age-groups was conducted in February and March, 2015. METHODS: Capillary blood samples collected from these individuals were used for the detection of both asexual and gametocyte stage parasites by microscopy, reverse transcriptase polymerase chain reaction (RT-PCR) and conventional nested PCR methods. The prevalence data as determined by microscopy and molecular methods were compared using chi-square tests. RESULTS: Parasitaemia from these asymptomatic infections ranged from 40 to 3,520 parasites/µl of blood (geometric mean parasitaemia = 732 parasites/µl). The prevalence of asymptomatic P. falciparum carriage was 4.8% (10/209) and 13.9% (29/209) using microscopy and RT-PCR respectively. The overall prevalence of sub-microscopic infections in the total number of samples analysed was 9.1% (19/209) and 66% (19/29) of the asymptomatic infections. P. falciparum gametocytemia detected by microscopy was 1% (2/209) and 3.8% (8/209) by PCR. CONCLUSION: This is the first report of sub-microscopic asexual and gametocytes infections in the dry season in a seasonal malaria transmission area in Ghana. It has established that persistent latent malaria infections occur and that these could supply the source of parasites for the next transmission season. The findings highlight the presence of sub-microscopic infections and therefore the need for active case detection surveillance to eliminate "asymptomatic reservoir" parasites and consequently break the transmission of the disease in Ghana. FUNDING: Bill and Melinda Gates Foundation grant awarded to Noguchi Memorial Institute for Medical Research Postdoctoral and Postgraduate Training in Infectious Diseases Research (Global Health Grant # OPP52155); National Institutes of Health grant (NIH-NIAID RO1 # 1RO1AI099623) to MDW; European Developing Countries Clinical Trials Partnership (EDCTP)-West African Network of Excellence for Clinical Trials in TB, AIDS and Malaria (WANETAM) (Project code CB.07.41700.007).
BACKGROUND: We investigated the prevalence of sub-microscopic Plasmodium falciparum infections and gametocyte carriage in asymptomatic individuals in Navrongo in northern Ghana, an area of seasonal malaria transmission. DESIGN: A cross sectional study of 209 randomly selected participants of all age-groups was conducted in February and March, 2015. METHODS: Capillary blood samples collected from these individuals were used for the detection of both asexual and gametocyte stage parasites by microscopy, reverse transcriptase polymerase chain reaction (RT-PCR) and conventional nested PCR methods. The prevalence data as determined by microscopy and molecular methods were compared using chi-square tests. RESULTS: Parasitaemia from these asymptomatic infections ranged from 40 to 3,520 parasites/µl of blood (geometric mean parasitaemia = 732 parasites/µl). The prevalence of asymptomatic P. falciparum carriage was 4.8% (10/209) and 13.9% (29/209) using microscopy and RT-PCR respectively. The overall prevalence of sub-microscopic infections in the total number of samples analysed was 9.1% (19/209) and 66% (19/29) of the asymptomatic infections. P. falciparum gametocytemia detected by microscopy was 1% (2/209) and 3.8% (8/209) by PCR. CONCLUSION: This is the first report of sub-microscopic asexual and gametocytes infections in the dry season in a seasonal malaria transmission area in Ghana. It has established that persistent latent malaria infections occur and that these could supply the source of parasites for the next transmission season. The findings highlight the presence of sub-microscopic infections and therefore the need for active case detection surveillance to eliminate "asymptomatic reservoir" parasites and consequently break the transmission of the disease in Ghana. FUNDING: Bill and Melinda Gates Foundation grant awarded to Noguchi Memorial Institute for Medical Research Postdoctoral and Postgraduate Training in Infectious Diseases Research (Global Health Grant # OPP52155); National Institutes of Health grant (NIH-NIAID RO1 # 1RO1AI099623) to MDW; European Developing Countries Clinical Trials Partnership (EDCTP)-West African Network of Excellence for Clinical Trials in TB, AIDS and Malaria (WANETAM) (Project code CB.07.41700.007).
Authors: Mônica da Silva-Nunes; Marta Moreno; Jan E Conn; Dionicia Gamboa; Shira Abeles; Joseph M Vinetz; Marcelo U Ferreira Journal: Acta Trop Date: 2011-10-12 Impact factor: 3.112
Authors: R Price; F Nosten; J A Simpson; C Luxemburger; L Phaipun; F ter Kuile; M van Vugt; T Chongsuphajaisiddhi; N J White Journal: Am J Trop Med Hyg Date: 1999-06 Impact factor: 2.345
Authors: Zulma Milena Cucunubá; Ángela Patricia Guerra; Jorge Alonso Rivera; Rubén Santiago Nicholls Journal: Trans R Soc Trop Med Hyg Date: 2012-12-02 Impact factor: 2.184
Authors: Chris Cotter; Hugh J W Sturrock; Michelle S Hsiang; Jenny Liu; Allison A Phillips; Jimee Hwang; Cara Smith Gueye; Nancy Fullman; Roly D Gosling; Richard G A Feachem Journal: Lancet Date: 2013-04-15 Impact factor: 79.321
Authors: Maxwell Appawu; Seth Owusu-Agyei; Samuel Dadzie; Victor Asoala; Francis Anto; Kwadwo Koram; William Rogers; Francis Nkrumah; Stephen L Hoffman; David J Fryauff Journal: Trop Med Int Health Date: 2004-01 Impact factor: 2.622
Authors: Sammuel L Nsobya; Sunil Parikh; Fred Kironde; George Lubega; Moses R Kamya; Philip J Rosenthal; Grant Dorsey Journal: J Infect Dis Date: 2004-05-24 Impact factor: 5.226
Authors: Philippa A West; Natacha Protopopoff; Mark Rowland; Emma Cumming; Alison Rand; Chris Drakeley; Alexandra Wright; Zuhura Kivaju; Matthew J Kirby; Franklin W Mosha; William Kisinza; Immo Kleinschmidt Journal: PLoS One Date: 2013-06-07 Impact factor: 3.240
Authors: Simon Kasasa; Victor Asoala; Laura Gosoniu; Francis Anto; Martin Adjuik; Cletus Tindana; Thomas Smith; Seth Owusu-Agyei; Penelope Vounatsou Journal: Malar J Date: 2013-02-13 Impact factor: 2.979
Authors: J Teun Bousema; Louis C Gouagna; Chris J Drakeley; Annemiek M Meutstege; Bernard A Okech; Ikupa N J Akim; John C Beier; John I Githure; Robert W Sauerwein Journal: Malar J Date: 2004-06-17 Impact factor: 2.979
Authors: Noah T Ventimiglia; Emily M Stucke; Drissa Coulibaly; Andrea A Berry; Kirsten E Lyke; Matthew B Laurens; Jason A Bailey; Matthew Adams; Amadou Niangaly; Abdoulaye K Kone; Shannon Takala-Harrison; Bourema Kouriba; Ogobara K Doumbo; Phillip L Felgner; Christopher V Plowe; Mahamadou A Thera; Mark A Travassos Journal: Sci Rep Date: 2021-07-13 Impact factor: 4.379
Authors: Ruth Ayanful-Torgby; Neils B Quashie; Johnson N Boampong; Kim C Williamson; Linda E Amoah Journal: PLoS One Date: 2018-06-15 Impact factor: 3.240
Authors: Melina Heinemann; Richard O Phillips; Christof D Vinnemeier; Christina C Rolling; Egbert Tannich; Thierry Rolling Journal: Malar J Date: 2020-10-12 Impact factor: 2.979